Changes in Carrying Value of Goodwill (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($)
Goodwill [Line Items]
Balance as of December 31, 2019	$ 468,413
Cumulative translation adjustment	764
Balance as of September 30, 2020	482,043
C Technologies, Inc.
Goodwill [Line Items]
Goodwill arising from Acquisition	293
Balance as of September 30, 2020	142,314
Engineered Molding Technology
Goodwill [Line Items]
Goodwill arising from Acquisition	12,573
Balance as of September 30, 2020	$ 12,600

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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